Reimbursement for apprenticeship

I am a 4th year apprentice about to finish up school. Some background, I started my apprenticeship with my company and for all four years of my apprenticeship I’ve been paying out of pocket (about 7000 dollars for all four years) the company told me they wouldn’t pay for it. Now that I am almost finished they want to reimburse me for all four years but they want me to sign a contract saying I’ll stay for two years. I was wondering if this is normal and if it is worth doing?

Edit: I work maintenance in a union shop making a little more than 27 an hour I’m just wondering if it’s worth my time to stay or if I should think about finding another opportunity once I get my journeyman’s papers